Jump to content

Talk:Melamine

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Structural diagram is incorrect

[edit]

--the diagram contains no carbon. The diagram and formula C3H6N6 are inconsistent. --Perdustin (talk) 17:42, 27 January 2023 (UTC)[reply]

It does, in organic chemistry diagrams the carbon atoms are not written, they are at the points where the bonds (lines) meet (its a short writing form because there is no organic compound without carbon) so they are in the ring between the nitrogen atoms. 80.128.193.55 (talk) 17:38, 12 February 2023 (UTC)[reply]

Milk powder for babies containing Melamine claim two lives

[edit]

http://ap.google.com/article/ALeqM5j9TWJGihXFri_4iWWPS7iDjKrT5gD935Q0NO0

--81.234.213.165 (talk) 11:09, 15 September 2008 (UTC)[reply]

Is this something that should be included at the beginning of the article?Igloo321 (talk) 07:26, 5 October 2008 (UTC)[reply]

No, this is info for 2008 Chinese milk scandal. Such details aren't about Melamine per se, but rather about an event which had melamine as one of it's components. NJGW (talk) 07:35, 5 October 2008 (UTC)[reply]

Not Microwave Safe

[edit]

I would like to see some information about why melamine utensils are not microwave safe. Is it because they might release formaldehyde or other toxic compound? Or is it simply because the melamine might melt?

--Qole 14:54, 4 June 2006 (UTC)[reply]

I don't have any specialized knowledge on the subject, but I know that my melamine plates get pretty hot in the microwave. So I don't figure it's any toxic stuff. NickelShoe (Talk) 15:21, 5 June 2006 (UTC)[reply]
I think you just nailed it on the head right there; its organic and it really heats up. That means at some point, its going to undergo decomposition, and that point will be a lot sooner than a material based on glass. —Preceding unsigned comment added by 70.162.242.234 (talk) 21:25, 12 October 2008 (UTC)[reply]
Melamine will become brittle over time if used in a microwave. It's not due to a safety/toxicity issue. 57.135.233.22 (talk) — Preceding undated comment added 09:37, 25 June 2024 (UTC)[reply]

Disambiguation

[edit]

The name of this article rhymes with melanin, the substance responsible for skin pigmentation. Is it appropriate to note this fact by providing a link from one to the other? --Folajimi 15:55, 5 June 2006 (UTC)[reply]

If it's just an "isn't this neat" random info fact, then no. If you are genuinely concerned that someone would possibly confuse melanin with melamine, then perhaps. The only reason to provide above the fold type links to (topically) unrelated articles is if people might mistakenly come to this page instead of the other one. -- 21:39, 12 December 2006 (UTC)

Cleaning Eraser action

[edit]

I'd like to know more about *how* those "magic" cleaning erasers made from melamine work. How are they able to clean surfaces that normal detergents and solvents cannot? --72.202.150.92 02:42, 12 December 2006 (UTC)[reply]

Check out Magic Eraser. NickelShoe (Talk) 02:48, 12 December 2006 (UTC)[reply]

Dishwasher Safe

[edit]

I came to this page to find out if Melamine is dishwasher safe. Would be nice to add info if anyone knows.—The preceding unsigned comment was added by 60.241.91.114 (talkcontribs).

Did you check the bottom of the plate? They're usually dishwasher safe, but you might be careful with heat drying them. NickelShoe (Talk) 17:02, 7 January 2007 (UTC)[reply]
I'd second checking the bottom. I have some pet food bowls that say "100% Melamine / Dishwasher safe / Do not microwave" and it's likely you would find similar wording on your items. Marc Kupper (talk) (contribs) 21:41, 6 May 2007 (UTC)[reply]
We got Melmac dishware for our wedding and 40 years later some of those plates are still in use by our daughter. They are nearly indestructable, except putting one over a gas jet will do the job. NStahl (talk) 20:32, 22 January 2008 (UTC)[reply]

Toxicity

[edit]

When ingested in large amounts the substance may have effects on the kidneys and bladder, resulting in stone formation [1].  Andreas  (T) 22:10, 30 March 2007 (UTC)[reply]
I will be donating my melamine bowl and spoon to the local refuge for stray dogs. Nothing will be left to chance because included with the bowl will be a large bag of xylitol sweetened dog biscuits, more than enough for each and every dog in the pound. I'm generous like that:) Signed IP attached. (195.189.142.235 06:06, 22 April 2007 (UTC))[reply]

Use in Fertilizer

[edit]

I hope someone is preparing information on how and why it's used in fertilizer. —The preceding unsigned comment was added by NStahl (talkcontribs) 09:45, 31 March 2007 (UTC).[reply]

I could not find information of how melamine is broken down to produce nitrogen compounds that plants can take up. Is is ammonium ions or nitrates?  Andreas  (T) 15:08, 2 April 2007 (UTC)[reply]
The bacterial metabolism cite I added under the toxicity section indicates that melamine degrades to ammonia via cyanuric acid and then allophanate. Abby Kelleyite 23:23, 26 April 2007 (UTC)[reply]

the LD50 scores for rats don't add up in the text. look at them again someone. —Preceding unsigned comment added by 86.16.239.23 (talk) 11:10, 22 January 2009 (UTC)[reply]

Cyromazine

[edit]

It appears to me that melamine found in Chinese gluten was not used as a fertilizer, but is a residue of the pesticede cyromazine. The chemical structure of cyromazine is very similar to that of melamine.  Andreas  (T) 21:39, 6 April 2007 (UTC)[reply]

Formula and description: http://www.generalchem.cn/template/crop/Cyromazine.htm  Andreas  (T) 22:28, 6 April 2007 (UTC)[reply]

Melamine from coal

[edit]

The NYT reported melamine as being produced from coal but did not specify the process beyond being done in "boilers". Perhaps this is some sort of Fischer-Tropsch process. I'm looking for some reference that says this but if anyone else can find one, please add it here and in 2007 pet food crisis. Abby Kelleyite 07:23, 30 April 2007 (UTC)[reply]

I have added some info re coal gasification in urea production and info that the manufacturer reported in the NYT produces both urea and melamine. Need that final link that says that melamine is also produced via goal gasification. Abby Kelleyite 14:20, 30 April 2007 (UTC)[reply]
Btw, for anyone trying to look more into the coal gasification thing, there is a nice illustrative diagram in a document proposing building a similar operation in Alaska on page 4 of the pdf. http://www.gasification.org/Docs/2006_Papers/22JOHN-Paper.pdf I don't think it's enough on point to include as a ref in the article but might help people find other refs. Abby Kelleyite 18:49, 30 April 2007 (UTC)[reply]

I have performed a fairly comprehensive patent and literature search and can find no literature relevant to making melamine from "coal". The major pathways for synthesis are (1) from cyanamide or dicyandiamide (2) from urea (thermally) or (3) from carbon dioxide and ammonia. Probably the urea pathway (2) is the most economical at this time; the older pathway (1) requires making calcium cyanamide which requires substantial electrical power, and is thus more costly. Since the Chinese company in question, according to their website, produces only urea and melamine they must employ the second (2) process.

Fischer-Tropsch is a good, albeit somewhat costly way to make hydrocarbons but is not a pathway to nitrogen-rich compounds such as melamine. I <<speculate>> that coal might be used as a source of carbon to make the urea (from carbon dioxide and ammonia) but have no literature to support this contention. (Khymyst01)

Thankyou for the info. I did find one reference regarding Fischer-Tropsch and nitrogen but I only have the abstract. Investigation on the Fischer-Tropsch Synthesis with Nitrogen-Containing Syngas over CoPtZrO2/Al2O3 Catalyst Dongyan Xu, Hongmin Duan, Wenzhao Li,* and Hengyong Xu Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China Received November 10, 2005 I would need someome who understands this sort of thing much better than me to see if it relevant. Abby Kelleyite 15:28, 2 May 2007 (UTC)[reply]
A little more verbiage from the newer NYT story (first May 3 story): "melamine scrap" which is not "pure melamine but impure melamine scrap that is sold more cheaply as the waste product after melamine is produced by chemical and fertilizer factories here." [2] —The preceding unsigned comment was added by AbbyKelleyite (talkcontribs) 17:54, 3 May 2007 (UTC).[reply]
The major motivation, btw, for adding the coal references is to indicate that what the NYT reporter appears to be talking about is not melamine resin scrap, which is an issue a number of people have raised. Abby Kelleyite 18:08, 3 May 2007 (UTC)[reply]
Another thing on the FT of coal, this brief reference notes that the standard FT used to create large hydrocarbons "also creates a lot of molecules in between, containing four to nine carbon atoms, which are considered waste products of the reactions." I'm wondering, if given this propensity to produce all these molecules, combined with the reference of FT involving nitrogen from above, might be a recipe for spitting out a waste product containing both melamine and cyanuric acid. Speculation, for now. Abby Kelleyite 17:03, 4 May 2007 (UTC)[reply]
It seems increasingly like Barboza is talking about melamine monomer but perhaps both kinds are used as NPN adulterants. Have you seen any reference anywhere that raises this as a possibility? It would be good to get the debate, if any, into the article for NPOV. Surely someone quotable has raised this possibility but I can't find it in english, anyway. Abby Kelleyite 18:44, 3 May 2007 (UTC)[reply]
I haven't seen anybody in mainstream media looking into this. In his Apr 30 article, Barboza said melamine costs "about $1.20 for each protein count per ton". Melamine is about 66% nitrogen while protein has 16%. Assuming a "protein count" = 1% protein, his description means one can replace 1 ton of pure protein by 0.25 ton of melamine at a price of $120. That gives a melamine price of $480/ton, or about 3840 yuan/ton. Compare that with the going price of urea in China (it takes 3 molecule of urea to make 1 molecule of melamine), Barboza's melamine does look more like the monomer. However, from a business point of view, waste melamine plastic would be much cheaper than even monomer (industrial grade of mixed by-product), somewhat less toxic and deliver almost the same amount of NPN... --Tsiaojian lee 21:28, 3 May 2007 (UTC)[reply]
I suspect that both may be being used, particularly with what you have reported in regard to the "prior art" of using ground urea-formaldehyde resin. There was mention in one of the barboza pieces, if I remember correctly, that the melamine scrap he was talking about used to be free and now is auctioned off. I seriously suspect that it is a mixture of carbon, hydrogen, nitrogen of varying compositions (including melamine and cyanuric acid) produced as a residue in the coal->urea->melamine process, much like the mix of hydrocarbon waste in the standard FT coal gasification. I hope (because of the expected lower toxicity) that ground melamine resin may be the more common contaminant. Both companies he's focused on so far, though, have been chemical manufacturers. I fear there may be a lot of this glop. Anyway, if you find even a chinese language only ref re ground melamine resin, I'd add it for balance. Abby Kelleyite 12:41, 4 May 2007 (UTC)[reply]
After doing some research, I re-wrote the synthesis section of melamine. What you suspected indeed looks VERY LIKELY!! The solid from melamine waste water contains mostly melamine but also some cyanuric acid etc. Since it's an unwanted waste it would also be very cheap. That also explains the cyanuric acid... --Tsiaojian lee 20:41, 4 May 2007 (UTC) Added from user talk page to help others follow the developments. Abby Kelleyite 02:33, 5 May 2007 (UTC) Some discussion copied over from the 2007 pet food crisis discussion page as an aid for anyone following this topic. 24.151.115.12 20:02, 5 May 2007 (UTC)[reply]

So now I'm wondering if recent changes in the process (signaled perhaps by the 2005 paper above) have resulted in either (or both) more waste being produced or an increase in the percentage of cyanuric acid in the effluent and an increase in the toxicity of the melamine cyanuric acid crystals. Any leads/thoughts apreciated. Abby Kelleyite 01:55, 6 May 2007 (UTC)[reply]

This reference demonstrates that cyanuric acid production via urea pyrolysis (thermal decomposition) varies tremendously depending upon such variables as temperature and pressure. There is a helpful temperature-dependency reaction scheme diagram on page 7 of the pdf Shaber et al., Study of the thermal decomposition of urea (pyrolysis) reaction and importance to cyanuric acid production, American Laboratory, August 1999, so if there were significant changes in the process for producing melamine, it would not be surprising to see a significant change in the amount of cyanuric acid produced in waste. Abby Kelleyite 03:23, 6 May 2007 (UTC)[reply]

Btw, did we ever get the full paper from the nitrogen reference or were we staying with the abstract even after Tsiaojian lee provided the synthesis equations? Abby Kelleyite 22:54, 15 May 2007 (UTC)[reply]

Redirects to 2007 pet food crisis

[edit]

I pointed the current flags to the [2007 pet food crisis] because at the moment there is much more info there, but I am no wiki policy expert. If there is some other way to indicate that someone reading these sections should look there for more info that works for me. Also, it would help a reader if they were pointed to the proper subsections of that rather large article, but I don't know how to do that. For toxicity, there is a subsection on "melamine and cyanuric acid in pet sickness" and for widespread use in china, there is a subsection on "melamine production and use". Thanks for any help the more wiki knowledgable can provide. Abby Kelleyite 14:31, 30 April 2007 (UTC)[reply]

Melamine products

[edit]

Here is directory of Melamine products from China:

Melamine dinnerware is an important part of Industrial history and was produced in the United States in large quantities circa 1940's to 1970's. Much history on differnet manufacturers here:

This supplier offers NPN in the form of "Protein powder"

One wonders what the Non-Protein Nitrogen (NPN) is.

--jwalling 01:17, 2 May 2007 (UTC)[reply]

A contributor over in the 2007 pet food crisis article has added info and cites (mostly chinese language) stating that ground urea-formaldehyde resin is a well known NPN additive and (adulterant in non-ruminant feed). I cannot evaluate the validity of the chinese language citations but note this as a possible answer to your question of what that NPN might be. Abby Kelleyite 15:43, 2 May 2007 (UTC)[reply]
NPN = nitrogen-containing chemicals that are not protein, but can be utilized by (at least some) animals for nutrition. Around the world, they are given to ruminants (see e.g. NPN for Cattle and Sheep and a huge manual by FAO) becuase ruminant stomaches can convert them into protein, and they are cheaper than protein-rich feed (e.g. soybeans). Note that the form and feeding of NPN are strictly regulated, as careless use of can poison the animals. In other words, ground-up scrap urea-formaldehyde resin is unlikely to be an acceptable NPN.
Now on urea-formaldehyde resin as an adulterant. AbbyKelleyite's "protein powder" seller above (the very company suspected by FDA right now!!) is very typical of what I find -- proclaimed protein additive with >100% crude protein yet not admitting it's urea-formaldehyde or any NPN. On this Chinese journal website you could see 2 english titles, suggesting that the problem is probably serious enough to warrant research on its testing. Another FAO document mentioned urea-formaldehyde as a common adulteration in fish meal. --Tsiaojian lee 03:12, 3 May 2007 (UTC)[reply]

Toxicity in humans?

[edit]

I am not an expert on research in chemistry or biology, but could somebody who is more informed on this subject look into Melamine toxicity in humans? There are recent concerns that Melamine has entered the US food supply through animal feed and the FDA has yet to say with any certainty that the tainted wheat gluten and other products haven't been used in human foods. I can't be the only one who came to this wiki entry to find information on toxicity in humans, yet the entry on toxicity only discusses animal toxicity. My questions would be: a) are the levels of contamination found in wheat gluten and other contaminated products at high enough levels to cause problems in humans? b) have there been any cases of Melamine poisoning in humans, and what were the effects? c) what treatment or tests, if any, are available to detect human Melamine poisoning? These are my concerns, and if anybody is able to find reputable information to address them, I (and likely others) would greatly appreciate your efforts. Mardish 20:05, 3 May 2007 (UTC)[reply]

As far as I have been able to determine, that one line above the current event box is what is known prior to this incident. FDA/USDA have two joint press releases specific to pork and chicken and low risk in humans. The cites are in 2007 pet food crisis under the Impact on human food supply section. Abby Kelleyite 20:46, 3 May 2007 (UTC)[reply]
Added them here at begiining of current event portion of the toxicity section. More information going on over at 2007 pet food crisis including discussion page re: splitting article. Abby Kelleyite 20:58, 3 May 2007 (UTC)[reply]
Just wanted to mention that there are also two brief statements regarding pre-current event info in the Regulations section above toxicity. Abby Kelleyite 21:34, 3 May 2007 (UTC)[reply]
Melamine has 2 kinds of toxicity: short term (acute) and long term (carcinogenic). On its MSDS sheet, the current LD50 oral dose is >3000mg/kg based on rat model, about the same level as table salt. For an adult of 75kg (165lb), that translates to 225g (8oz), which is quite a lot. Note that this is just an educated guess since it's not based on human data.
I am able to find 2 reported cases of human poisoning involving melamine. One is from inhaling water repellent containing melamine, and the other from inhaling hydrocyanic acid from burning melamine resin plates. Both are quite bizzare and cannot provide a estimate of melamine poisoning by oral means. --Tsiaojian lee 03:58, 4 May 2007 (UTC)[reply]

The section on toxicity claims that melamine breaks down into guanidine and ammonia, and quoted a litigation website as a source to claim that guanidine is used as a muscle stimulant, and that ammonia is a poison. I have removed the source, as this is a website of a law firm trying to get people to sue the pet food companies, not a primary scientific source.

I have also removed the comments about guanidine and ammonia. Both terms are wikilinked, and if people want to know their properties, they're just a click away. The statements are inflammatory at best. Both are found in the urine of healthy individuals. Ammonia is better known as a fertilizer than a poison, and is only toxic if you inhale a lot of the fumes. Oral toxicity from ammonia is unlikely in food: It would stink too much for anyone to want to eat it. I looked in Google scholar and the British Pharmacopoeia, and couldn't find anything about guanidine itself being used as a stimulant, although guanidine derivatives seem to be used pharmacologically. --Slashme 08:10, 7 May 2007 (UTC)[reply]

"On May 7, the USDA and the FDA issued a joint press release reflecting the combined judgment of five federal agencies with regard to the risk to humans in consuming meat from animals fed feed contaminated with tainted pet food scraps, concluding: "There is very low risk to human health" in such cases involving pork and poultry."

It is amusing (and ridiculous) that although at least hundreds or thousands of animals have been killed by something that is not understood, the US government is now officially assuring us all that humans that eat such animals fed the same unknown poisons are in no danger.-69.87.203.178 13:29, 8 May 2007 (UTC)[reply]

So, they have presumably done a sophisticated, high-tech risk analysis -- of an unknown risk! It'll be interesting to read the peer-reviewed scientific papers that will come out of this... Don't worry about eating fish -- we BELIEVE they are safe... "FDA: The Faith-Based Dining Administration" [3] -69.87.204.79 01:56, 10 May 2007 (UTC)[reply]

From 2009: Melamine, Powdered Milk, and Nephrolithiasis in Chinese Infants Symptom info from Kidney disease from powdered infant formula-based melamine exposure in Chinese infants. The Woodlands, TX: American Society of Pediatric Nephrology TABLE 1 SIGNS AND SYMPTOMS REPORTEDLY ASSOCIATED WITH MELAMINE EXPOSURE FROM POWDERED INFANT FORMULA IN CHINESE INFANTS • Unexplained crying in infants, especially when urinating. • Vomiting. • Unexplained fever secondary to urinary tract infection/bacteremia secondary to urinary stasis resulting from obstruction. • Macroscopic or microscopic hematuria. • Acute obstructive oligo-anuric kidney failure. • Stones discharged while passing urine. • High blood pressure, edema, elicitable flank pain. Abby Kelleyite (talk) 21:51, 13 August 2009 (UTC)[reply]

Indifference, Terrorism, War

[edit]

How are we in these times to distinguish the current melamine/food-chain scare from gross commercial indifference, subtle political terrorism or a covert military act of war ?

Well as unfortunate as the death of thousands of pets are, it seems unlikely that killing them would be an act of war. Also, it seems unlikely that China would gain any advantage as a result of this but it's going to cost them financially so I'm not particularly sure why they would engage in 'political terrorism' Nil Einne 10:19, 8 May 2007 (UTC)[reply]

Contamination of Contaminants

[edit]

Is there any research and surveillance being done to uncover contaminants of melamine and other industrial chemicals with links -- however small -- to the food chain ?

This is important because some industrial contaminants accumulate in the tissues of living things, so ANY detectable amount is far too much. Such contaminants include the heavy metals -- cadmium, lead, etc. Lead is a probable contaminant because it is/was widely used as a paint pigment. Has China outlawed such uses and removed leaded paints from buildings and industrial equipment where it might inadvertantly get into products ?

Just added a section reviewing detection of melamine in food. Please feel free to comment. --Tsiaojian lee 21:15, 6 May 2007 (UTC)[reply]

Chemical Reactions to Reverse Crystaluria??

[edit]

This question is posed to readers who can give insight on what non-toxic chemicals/drugs might be investigated to react with Melamine/Cyanuric acid complex to reverse the crystalurea that leads to renal failure.

Recalling that in diabetic ketoacidosis, acetoacetic acid and acetone are produced in high levels (80mg/dl or more). Question: Invitro can acetoacetic acid or acetone's keto group react with the amino group of Melamine to make a more soluble product?

We need more information reagarding the reactions that Melamine can undergo at physiologic ph.

71.127.24.125

This might be premature, as we're not even sure that Melamine itself is the culprit, or whether it's just a marker for another agent. --Slashme 15:19, 7 May 2007 (UTC)[reply]
Ditto that. The quick & dirty way to figure out the culprit is direct animal experiments -- a millenia-old method in toxicology. Just feed lab cats/dogs melamine with other chemical suspects at various dosage combinations. It should become clear soon what causes the acute intoxication. It may not explain the underlying mechanism. But sitting in a lab & staring at those crystals is not an effective short-term solution. --Tsiaojian lee 17:12, 7 May 2007 (UTC)[reply]
Before you use animals in testing antidotes it makes more sense to first see if the reaction being looked for can occur in the test tube. People should not be so casual about animal experiments. It is also wasteful. —Preceding unsigned comment added by 71.127.23.22 (talk) 02:45, 19 September 2008 (UTC)[reply]
Iso-triazines may be reformed by reaction with chromic acid to produce quinone (harmless vitamin K). Appropriately, this same reaction may be produced by consuming low pH foods that are high in chromium, such as vinegar and romaine lettuce. --Gustable (talk) 05:20, 1 October 2008 (UTC)[reply]
Please provide a reference that supports this and explains the connection to Melamine. You seem to feel this is very important, but have yet to proved a source for it. NJGW (talk) 05:24, 1 October 2008 (UTC)[reply]
Following some searching through older pages I found the reference I was looking for on the page devoted to Aniline. Aniline is not an Iso-triazine, yet is an aromatic amine. Experiential evidence has supported that this longshot does convert what I would assume to be unreacted aniline impurities from the melamine preparation process into quinone. This may also remediate the other triazines experiencing a change in equilibrium. I hope this is sufficient. --Gustable (talk) 02:51, 2 October 2008 (UTC)[reply]
Unless there is a journal article or some other very reliable source discussing this in relation to Melamine, this is novel synthesis of other data (a form of original research). NJGW (talk) 05:07, 2 October 2008 (UTC)[reply]

Melamine toxicity in ruminants

[edit]

Melamine toxicity in ruminants

Melamine toxicity.

I have been surprised that in so many articles on melamine toxicity people are saying that before that pet food contamination 'the only known risk was to rodents'. Looking in the CAB Abstracts Archive I found a paper that shows crystalluria in sheep fed melamine for 11 days (Clark, R. 1966. Melamine crystalluria in sheep. CAB Record Number: 19671407708). This should be of interest to toxicologist especially as melamine is now being found widely in different animal feeds. RT —The preceding unsigned comment was added by 194.131.255.12 (talk) 10:53, 9 May 2007 (UTC).[reply]

A new survey on pet deaths

[edit]

Survey To Quantify Pet Deaths From Tainted Food I have been so tired from all the recent developments, but I am getting back at it. This is all too important. Abby Kelleyite 15:10, 15 May 2007 (UTC)[reply]

Not sure whether it should be in main article. Abby Kelleyite 15:14, 15 May 2007 (UTC)[reply]

Other similar surveys are being done by AAVLD, FDA and some state public health agencies. Currently no statistical analysis (aside from geographical location) is available. The case statistics may explain the discrepancy of melamine/CA toxicity between earlier animal experiments and actual feeding by consumers. E.g. older, sicker animals or certain breeds could be much more affected than the rest. --Tsiaojian lee 18:57, 15 May 2007 (UTC)[reply]

More recent photos on crystal formation in kidney tubules

[edit]

There are more up-to-date photos showing crystals in both prox and distal tubules with oxalate-type crystals in the former, while the latter seem to be associated with attenuation and loss of epithelium. [4] Abby Kelleyite 21:32, 15 May 2007 (UTC)[reply]

There is also evidence of interstitial edema Abby Kelleyite 22:14, 15 May 2007 (UTC)[reply]

password problems

[edit]

I just wanted to warn everyone that my password got hacked at Daily Kos. I've changed it now and I think the problem is under control. You may want to change yours here as well. It is best to be safe. Be sure to choose something with a strong level of protection. Abby Kelleyite 20:35, 15 May 2007 (UTC)[reply]

Toxicology study and AAVLD survey results

[edit]

The AVMA has some summary information on the AAVLD survey of the 347 cases that met diagnostic criteria for "pet food-induced nephrotoxicity" from April 5-June 6 [5] and UCDavis has info on the first published toxicology study looking at melamine and CYA ingestion in cats conducted after the recall. [6] Abby Kelleyite (talk) 22:56, 20 November 2007 (UTC)[reply]

More on the survey from Michigan State University including some comments re: potential for chronic toxicity. [7] Abby Kelleyite (talk) 17:46, 29 November 2007 (UTC)[reply]
And here's the AAVLD proceedings from their october meeting. Page 29 reports on the survey. Toxicology session findings start at page 100. Abby Kelleyite 20:33, 30 November 2007 (UTC)[reply]
Looking at this new press release from MSU, I fear that in my apparent role as de facto editor in charge of adding new science info here, I may have made some errors in attribution or emphasis of new information from the AAVLD meeting in October. My attempt has been to add information, with references, to help others reach their own conlusions about the science. I have neither the qualifications nor the inclination to apportion credit and wish to apologize to any of the involved individuals and institutions for any errors or ommissions on my part, and wanted to assure everyone involved that I have no affiliation with any of the involved institutions and that any errors I have made are in good faith. As with any wikipedia article, anyone is welcome to edit. Abby Kelleyite (talk) 19:34, 7 December 2007 (UTC)[reply]

Proposed merger of Reported widespread use in Chinese feed and food section

[edit]

An editor suggested merging this section with 2007 pet food recalls without additional comment. While that article and Chinese protein export contamination are the main articles for the information in this section, I think that the brief summary information provided here offer valuable context for the recent toxicology infomation and governmental advisories in the preceding sections. I would, however, be interested in hearing what anyone else thinks about this. Abby Kelleyite (talk) 15:44, 22 February 2008 (UTC)[reply]

Moved from article

[edit]

I removed the following text from the "See also" section because it was out of place, but it may be useful for other editors, so I've moved it here:

New article available describing finding melamine in seafood samples after the recall and the method used:
Determination and Confirmation of Melamine Residues in Catfish, Trout, Tilapia, Salmon, and Shrimp by Liquid Chromatography with Tandem Mass Spectrometry
Wendy C. Andersen,*† Sherri B. Turnipseed,† Christine M. Karbiwnyk,† Susan B. Clark,‡ Mark R. Madson,‡ Charles M. Gieseker,§ Ron A. Miller,§ Nathan G. Rummel,§ and Renate Reimschuessel§
Animal Drugs Research Center and Denver District Laboratory, U.S. Food and Drug Administration, Denver Federal Center, P.O. Box 25087, Denver, Colorado 80225-0087, and Center
http://www.ncbi.nlm.nih.gov/pubmed/18494486

-- Ed (Edgar181) 15:02, 8 August 2008 (UTC)[reply]

Melamine Structure doesn't show carbon

[edit]

The structure at the top of this article should show a "C" atom at each of the nodes. The melamine ring actually is composed of alternating C and N atoms. —Preceding unsigned comment added by 71.131.4.138 (talk) 21:01, 11 September 2008 (UTC)[reply]

It is not necessary to include the C labels - the image is a skeletal formula.
Ben (talk) 21:44, 11 September 2008 (UTC)[reply]

Melamine in milk powder

[edit]

This latest development may be worth putting in the article BBC asia-pacific/NZherald. Reports coming out suggest at least one baby has died Reuters. --Zven (talk) 08:50, 14 September 2008 (UTC)[reply]

Uh - a lot has been added on this - but I would oppose adding more than perhaps one sentence yet - Wikipedia is not a newspaper - and all this is still in the process of happening - an article here should not be caught in any current excitement, but should reflect the final judgment as it is normally done a year or so later (generally, in other cases, information that nobody will be interested in anymore in, say, 10 years, should not be included at all). 65.37.189.161 (talk) 16:38, 17 September 2008 (UTC)[reply]
I think we need more than one sentence. In particular I'd like to see an encyclopedic explanation (not reportage) of the chemistry behind why someone would add toxic melamine to milk. Melamine isn't a protein, so just what sort of "protein measurement" was being hoodwinked here? I'd also like some description of likely mechanisms for its harm. I've heard reports of "kidney stones", which are usually painful rather than fatal. What's so different about these ones? Are the stones fatal? Made of solid melamine? Or are they just simultaneous symptoms with some other mechanism actually causing the deaths? Andy Dingley (talk) 16:47, 17 September 2008 (UTC)[reply]
There is conflicting information in the article. With reference to baby powder issue, the article states: "Melamine which is a banned substance in China...". However, elsewhere in the article it states: "China is the world's largest exporter of melamine, while its domestic consumption still grows by 10% per year." The second statement would be incredible if Melamine was indeed a banned substance in China. Perhaps it is a banned substance in foodstuffs? Bernard S. Jansen (talk) 00:59, 19 September 2008 (UTC)[reply]
"Melamine, which is a banned substance in China" sounds more like a patriotic statement. I am changing it to "classified controlled substance". However, I feel even my modification is inaccurate. Someone who is familiar with China needs to modify that to controlled/classified substance of some classification under Chinese law. Otherwise, that statement should be removed altogether. What is the classification of melamine in China under which melamine is controlled? Someone with Chinese legal and consumer expertise please elaborate. It is not banned substance because China is world's capital of melamine-ware production.Hence Jewish Anderstein (talk) 12:12, 19 September 2008 (UTC)[reply]

There is a discrepancy between the China milk scandal section and the main Milk Scandal article. This section reports 4 infant deaths but the main article reports 6. It seems that the larger number is more recent. <http://www.cnn.com/2009/WORLD/asiapcf/01/22/china.tainted.milk/index.html> I suggest it be changed to 6 and a new reference given. Barjeconiah (talk) 03:26, 5 July 2009 (UTC)[reply]

Toxicity - US Statements - Dates

[edit]

Under Toxicity, US Statements subheading, there are a series of dates listed with date and month, but no year, eg: April 1. Can someone who knows when these statements where made add a year? -Bernard S. Jansen (talk) 01:02, 19 September 2008 (UTC)[reply]

The old US statements were from 2007 and I believe they have been moved to either the 2007 pet food recalls article or its associated talk page. Abby Kelleyite (talk) 22:50, 13 August 2009 (UTC)[reply]

Research into what non-toxic substances dissolve Melamine

[edit]

Given the renal crystalization is a reoccuring problem, some research needs to be done to find some non-toxic substance that will dissovle those crystals. Something maybe with an unhindered keto group, that is also water soluble to react with the amino groups.

71.127.23.22 (talk) —Preceding undated comment was added at 02:41, 19 September 2008 (UTC).[reply]


I'd like to second this request. Note that the insoluble complex originates as a base pair like interaction between melamine and cyanuric acid. (The picture[8] says a thousand words; but also consider that layers of these assemblies should stack up eagerly) Someone must be working on this - but it may not be published yet but still be floating around at seminars or conferences.

A. Does the melamine-cyanuric acid complex undergo covalent cross-linking after it is formed?

  1. This might occur spontaneously - if you look at that picture, every N has three bonds and every O has two. You can write these molecules with N+ and O- and I think that this nucleophile might consider attacking the carbon of an adjacent layer if orientation and other factors allow it, but I'm not sure.
  2. Also bear in mind that the reaction that eventually causes fibrosis will be pouring peroxide, bleach, and other reactive oxygen species into this environment.
  3. The main question is: will antioxidants have any effect on these people, and if so will it be beneficial? Many of them are probably going to be taking traditional Chinese medicines with a strong antioxidant content, and everything they ingest ends up right there concentrated in the kidney tubule if it's not destroyed in the body.

B. Has anyone measured the solubility relationship between melamine and cyanuric acid, in the presence of various inorganic salts? Again, practically any salt you eat ends up right there (though the kidney has its own ideas about some of them) so in theory it might be possible to assist the breakup of the precipitate or if lucky prevent it from forming.

C. How sharp are these complexes and how much force is behind their growth? The crystals are fan-shaped and originate in large flat assemblies of molecules. Is some of the damage from the physical rupturing of cells in the kidney tubules? If so, it might be that the traditional Chinese medicines or modern anti-inflammatory agents will affect the response to this physical damage in a hopefully positive way.

Wnt (talk) 22:10, 22 September 2008 (UTC)[reply]

Toxicity incorrect

[edit]

The wiki lists the LD50 as 3000mg/kg, which is a completely nonsensical value. It probably needs to be micrograms instead of miligrams, but I haven't found a source for this fact. —Preceding unsigned comment added by 205.175.225.22 (talk) 22:11, 25 September 2008 (UTC)[reply]

Why is it nonsensical? See Melamine MSDS --Burntnickel (talk) 17:16, 30 September 2008 (UTC)[reply]
The issue is that the PH is correct in the kidneys for Melanine to crystalise. How you quantify the slow progressive nature of kidney failure from kidney stone growth is difficult. Studies in rodents such as mice do not directly translate to humans --Zven (talk) 07:11, 2 October 2008 (UTC)[reply]

The first sentence's reference to Chinese export contamination

[edit]

I don't think it is appropriate for the first sentence of the article to contain the clause "which has been implicated in the Chinese protein export contaminations." It is better to include such comment in a later sentence.Igloo321 (talk) 07:49, 5 October 2008 (UTC)[reply]

Good point, I changed the lead to say all that Melamine is in one sentence, though I left what melamine is most notable for in general in the lead. NJGW (talk) 07:52, 5 October 2008 (UTC)[reply]
I don't think the clause should be located inside the first general overview at all. It should be located in a later section discussing Chinese product contamination rather than just up front, as this is a chemistry article, not an article discussing scandals. ~electricRush (T C) 05:31, 2 November 2008 (UTC)[reply]
The lead should be a mini-article, explaining the most notable aspects of a topic. This aspect of the chemical is certainly it's most notable, though this may change in the future. NJGW (talk) 06:25, 2 November 2008 (UTC)[reply]
How come there isn't reference to the contamination of Chinese products exported to the UK?Fuzbaby (talk) 01:19, 21 June 2009 (UTC)[reply]

Why is testing expensive?

[edit]

It seems to me that testing ought not to be so expensive, won't melamine hydrolyze all the way to ammonia and CO2 if attacked with heat by, say, concentrated sodium hydroxide? Proteins, on the other hand, only break down as far as their individual amino acids, right - which will presumably remain somewhat attracted to the sodium due to their carboxyl groups. So why not test for the stuff (in foodstuffs) in a tube with concentrated NaOH solution and heat, and see how much ammonia comes off?

Last I checked, NaOH, water, and heat were pretty cheap, and detecting small amounts of ammonia as a gas is a very simple problem that could probably be approached with pH detection, additionally ammonia makes NH4Cl "clouds" when in the presence of HCl vapor, making isolated, optical detection by diffraction also possible, right?

Sure, lots of other things would fail this test too; but its not like they should be in food either, right? For example urea will probably fail it, as would simple amines in many drugs, even caffeine may decompose in a manner that would trigger failure of this test. The whole point however, is that carbohydrate, protein, and fat will NOT trigger a failure of this simple test, and those are the three primary organic components in most feedstuffs, and the problem with melamine contamination is NOT one of trace contamination, but rather, one of DELIBERATE contamination by crooks looking to substantially raise profits by diluting protein-containing material. —Preceding unsigned comment added by 70.162.242.234 (talk) 21:34, 12 October 2008 (UTC)[reply]

This sounds like a question best asked at the chemistry portal or wp:refdesk. All we can do here is repeat what the best sources say. NJGW (talk) 23:28, 12 October 2008 (UTC)[reply]
I think that what you describe has a problem that "ammonium X" will react with NaOH to release free ammonia as well. Since such salts are very cheap (fertilizer for example) the test could easily be defeated, even by 'accident'. Wnt (talk) 04:35, 17 January 2009 (UTC)[reply]

Use in Formation of Nitrogen-Doped Carbon Nanotubes

[edit]

Carbon nanotubes are quite unreactive to modification or addition of side groups. For this reason, it is often useful to nitrogen-dope (i.e. insert nitrogen atoms within the nanotube framework) so that modification can be possible and more uniformly distributed. When creating nanotubes through carbon vapour deposition, melamine can be used as a nitrogen source therefor. —Preceding unsigned comment added by 74.210.109.147 (talk) 04:25, 9 December 2008 (UTC)[reply]


Melamine detection; OpenWetWare project

[edit]

In Oct. 2008 I started a project to measure/detect melamine, called Melaminometer which is hosted as an open source project on [OpenWetWare]. OpenWetWare is also a wiki and I have a large number of ref. articles linked from it's project page. Since everyone here is also interested in melaminehttps://mekoong.com/melamine I wanted to mention this (and thank everyone here since a large part of the initial research used wikipedia), plus also point it out as a ref. for additions to this article. The proposed detection method uses an enzymatic approach, since certain bacteria have been found to degrade melamine (and Atrazine, a closely related substance). As of today this method is still waiting implementation by a fab lab. Jcline0 (talk) 04:57, 19 February 2009 (UTC)[reply]

Thanks for the advertisement.............. Fuzbaby (talk) 01:18, 21 June 2009 (UTC)[reply]


preparation - reaction mechanism urea -melamine

[edit]

this is over simplifed and the second part sort of incorrect. Co2 is evolved from the reaction of the water (released from the condensation of cyanuric acid with ammonia) with isocyanic acid — Preceding unsigned comment added by 122.109.117.3 (talk) 07:15, 14 April 2013 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just added archive links to one external link on Melamine. Please take a moment to review my edit. If necessary, add {{cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—cyberbot IITalk to my owner:Online 00:18, 7 January 2016 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just added archive links to one external link on Melamine. Please take a moment to review my edit. If necessary, add {{cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—cyberbot IITalk to my owner:Online 14:50, 9 February 2016 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just added archive links to one external link on Melamine. Please take a moment to review my edit. If necessary, add {{cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at {{Sourcecheck}}).

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—cyberbot IITalk to my owner:Online 12:33, 28 February 2016 (UTC)[reply]

Assessment comment

[edit]

The comment(s) below were originally left at Talk:Melamine/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Please note there is a mistake in the formulas where N(nitrogen) is supposed to be C(carbon)

Last edited at 13:09, 24 May 2007 (UTC). Substituted at 23:38, 29 April 2016 (UTC)

[edit]

Hello fellow Wikipedians,

I have just modified 6 external links on Melamine. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at {{Sourcecheck}}).

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 09:16, 10 November 2016 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just modified 5 external links on Melamine. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 00:08, 8 June 2017 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just modified 6 external links on Melamine. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 23:13, 4 September 2017 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just modified one external link on Melamine. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 02:43, 25 January 2018 (UTC)[reply]

Thank you!

[edit]

This was an amazing read, an all-around example of am well-written article. Yoleaux (talk) 19:36, 7 April 2020 (UTC)[reply]

Seeming errors in box "Properties"

[edit]

1) Solubility- "Solubility in water 3240 mg/ L (20 °C)". If this were true my worktops would have holes in them. Disagreement is rife on many sites, some quote the 3240 figure (from here?). It seems to me that this must be an error.

2) "Melting point 343C (decomposition)" seems incompatible with the following line "Boiling point: Sublimes". "Boiling point: Decomposes" seems OK but no entry at all for "Boiling point" would be better.

I am not qualified to correct these errors. Request somebody who is please do so. Pawprintoz (talk) 08:57, 22 February 2021 (UTC)[reply]

No C-C or C-H bonds.

[edit]

First sentence states melamine is an organic compound, but it lacks carbon-carbon or carbon-hydrogen bonds. Technically, one might argue that it is inorganic. However, there are certainly exceptions to the definition of an organic compound, but I am not qualified enough to discern if this compound has been, historically, considered organic. Altoeclef (talk) 03:25, 23 November 2022 (UTC)[reply]

Solubility in benzene?

[edit]

Is the compound soluble in benzene or is it not? The property list says both (moderately soluble and insoluble) can someone specify? (or maybe correct the mistake if there is any) 80.128.193.55 (talk) 17:46, 12 February 2023 (UTC)[reply]

A Commons file used on this page or its Wikidata item has been nominated for deletion

[edit]

The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion:

Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 05:23, 15 May 2023 (UTC)[reply]